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Updated: Jun 10, 2026
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Cell Population Analyses During Skin Carcinogenesis
Published on: August 21, 2013
Integrin A6 Cleavage in Mouse Skin Tumors
Manolis C Demetriou1, Kevin A Kwei, Marianne B Powell
1Department of Biological Sciences, University of Cyprus, Cyprus.
The Open Cancer Journal
|July 29, 2010
Summary
A truncated form of the α6 integrin (alpha6 integrin p24 variant), known as α6p, is found at higher levels in various skin cancers. Its presence suggests a role in tumor development and skin remodeling.
Area of Science:
- Cell Biology
- Cancer Research
- Integrin Signaling
Background:
- The α6 integrin (Laminin receptor) has a truncated variant, α6p (70 kDa), distinct from the full-length form (140 kDa).
- α6p is generated by urokinase-type plasminogen activator (uPA)-mediated cleavage of the extracellular domain on the cell surface.
- Previous studies linked α6p to prostate cancer, promoting tumor cell invasion and migration on laminin.
Purpose of the Study:
- To investigate the presence and role of the α6p integrin in other models of carcinogenesis, specifically skin cancer.
- To determine if α6p is induced in vivo, suggesting the involvement of the tumor microenvironment.
Main Methods:
- Analysis of α6p levels in normal mouse skin, chemically induced papillomas, squamous cell carcinomas, and melanomas.
- Assessment of α6p expression in tumors formed by injecting α6p-negative keratinocytes into nude mice.
Main Results:
- Low levels of α6p were detected in normal mouse skin, with significantly elevated levels in induced skin tumors and melanomas.
- Tumors developed in nude mice after injection of α6p-negative cells showed induced α6p expression, indicating in vivo generation.
- These findings suggest the tumor microenvironment influences α6p production.
Conclusions:
- Cell surface cleavage of α6 integrin to form α6p may represent a novel regulatory mechanism for integrins.
- The α6p integrin appears to play a significant role in skin tissue remodeling and carcinogenesis.
- α6p's induction in vivo highlights the importance of the tumor microenvironment in its generation and function.
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